Do not use PAGE_SIZE marco to calculate max_sectors per IO request. Driver code 
assumes PAGE_SIZE will be always 4096 which can do lead to wrongly calculated 
value if PAGE_SIZE is not 4096. This issue was reported in Ubuntu Bugzilla Bug 
#1475166.

Cc: <sta...@vger.kernel.org>
Signed-off-by: Sumit Saxena <sumit.sax...@avagotech.com>
Signed-off-by: Kashyap Desai <kashyap.de...@avagotech.com>
---
 drivers/scsi/megaraid/megaraid_sas.h      |    2 ++
 drivers/scsi/megaraid/megaraid_sas_base.c |    2 +-
 2 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas.h 
b/drivers/scsi/megaraid/megaraid_sas.h
index d236cc2..fab7602 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -388,6 +388,8 @@ enum MR_EVT_ARGS {
        MR_EVT_ARGS_GENERIC,
 };
 
+
+#define SGE_BUFFER_SIZE        4096
 /*
  * define constants for device list query options
  */
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c 
b/drivers/scsi/megaraid/megaraid_sas_base.c
index 92c5bbe..6204a66 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -4871,7 +4871,7 @@ static int megasas_init_fw(struct megasas_instance 
*instance)
 
 
        instance->max_sectors_per_req = instance->max_num_sge *
-                                               PAGE_SIZE / 512;
+                                               SGE_BUFFER_SIZE / 512;
        if (tmp_sectors && (instance->max_sectors_per_req > tmp_sectors))
                instance->max_sectors_per_req = tmp_sectors;
 
-- 
1.7.1

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